Question: If $a + b + c = -4$ and $x + y = 9$, what is $-9x - 9y + 8c + 8b + 8a$ ?
Solution: $= 8a + 8b + 8c - 9x - 9y$ $= (8) \cdot (a + b + c) + (-9) \cdot (x + y)$ $= (8) \cdot (-4) + (-9) \cdot (9)$ $= -32 - 81$ $= -113$